This study was done to investigate the antidiabetic effect of Glechoma hederacea LINNAEUS in Streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by intravenous injection of STZ at a dose of 45 mg/kg dissolved in citrate buffer. The methanol extract of Glechoma hederacea was orally administrated once a day for 6 days. The contents of serum glucose, triglyceride (TG), total cholesterol and Atherogenic Index (Al) were significantly decreased, but high density lipoprotein (HDL)-cholesterol and HDL-cholesterol/total cholesterol ratio (HTR) were significantly increased in Glechoma hederacea treated STZ-sample group compared to the those of STZ-control group. The content of hepatic lipid peroxide and activity of catalase were decreased, but content of glutathione as well as activities of glutathione-S-transferase and superoxide dismutase were increased in Glechoma hederacea treated STZ-sample group compared to the those of STZ-control group. The content of hepatic glycogen and activities of glucose-6-phosphate dehydrogenase, glucokinase were significantly increased, but activity of glucose-6-phosphatase was decreased in Glechoma hederacea treated STZ-sample group compared to the those of STZ-control group. These results indicated that methanol extract of Glechoma hederacea would have antidiabetic effect in STZ-induced diabetic rats.